1. Field of the Invention
The present invention relates to an electronic device having an electronic circuit incorporated therein, and to a housing for the same.
2. Description of the Related Art
In recent years, as the number of kinds of accessible peripheral devices is growing, note-type personal computers (hereinafter referred to as a note PC, for short) being a type of electronic device with built-in electronic circuits have become more convenient. Accordingly, the kind and number of ports (connectors) used to connect to the peripheral devices are being required to be increased. However, due to restricted mounting space, it is difficult to mount many connectors of various kinds all at once on a note PC itself. Thus, generally, each maker employs a connection configuration such that a separate unit having many connectors of various kinds mounted thereon is provided, and that the separate unit is detachably connected via a dedicated connector to the note PC. In many cases, in view of the wiring on the printed board and of the usability of other units and the note PC, the dedicated connector is mounted on the bottom face in the vicinity of the rear end of the note PC. When the dedicated connector is mounted on such a location, the bottom face of the housing of the note PC must be bored to mount the connector.
As a material for the bottom face side of the housing of the note PC, there is employed a metal plate-like member for the purposes, such as increasing the strength of a housing and securing the escape path for static electricity. Thus, a boring for mounting the connector is to be positioned around the end of the plate-like member. Also, at the rear end of the note PC, connectors, etc., are protruded outward from the housing, and the shell (metal outer shell section) of the connector is installed in the vicinity of the boring of the plate-like member.
In a note PC having such a structure, it is known that, when static electricity is applied to the shell of connector by the user's body coming close to the shell or by other actions, due to the static electricity, there are generated noises which cause the electronic circuit of the note PC to malfunction.
As a measure against such noises, there have been proposed a technique of plating the inner face of a plastic member constituting the outermost shell of a housing to thereby allow static electricity to escape to the plating film, and a technique of disposing a radiowave absorption sheet inside the housing to thereby prevent noises from entering the electronic circuit (refer to Japanese Patent Laid-Open No. 2001-308574, for example).
The hitherto proposed techniques, however, can pose problems, such as increasing the cost of note PCs, and hindering weight saving and reduction in thickness which are strongly requested of note PCs. In addition, in recent years, while reduction of adverse environmental effects as introduced when electronic devices are scrapped is strongly requested, the application of plating and radiowave absorption sheet can bring about significant adverse environmental effects.
These problems are posed not only by note PCs, but generally also by various electronic devices of which a noise countermeasure are requested.